Investors who put their money into an airport parking scheme that went into liquidation earlier this year are hoping for compensation after the Financial Conduct Authority announced it was taking legal action against those behind the scheme.

The Park First scheme, which collected more than £230m from thousands of people, offered returns of up to 12% to those who invested £20,000 a time on individual parking spaces at Gatwick and Glasgow airports.

But the FCA claims it was an “illegal collective investment scheme” that was “promoted to the public using false or misleading statements”.

Park First is just the latest in a string of schemes, many related to property, to have disappointed investors who were hoping for decent returns. While it is not always possible to sort the good from the bad, there are some steps you can take to protect yourself.

• “As a starting point, never invest in anything that you don’t understand,” says Patrick Connolly of financial advisers Chase de Vere. If something sounds highly complicated, or if the explanation of how the returns will be achieved doesn’t seem to stack up, ask questions. If it still doesn’t make sense, it might be a sign that something is wrong.

• It’s an old adage, but true: “If an investment seems too good to be true then it probably is,” says Connolly. “And if it is promoted with a very high interest rate then that means it is very high risk.” With returns on bank accounts still languishing in the low single figures, high rates of return may be a sign of high risk.

• “Stick to investing with reputable and established firms,” says James Daley, managing director of consumer group Fairer Finance. The FCA publishes a register of companies that it authorises – you can check it at register.fca.org.uk. It also has a list of unauthorised firms – these are firms that it has received complaints about, but do not assume that a company that does not appear on this list is legitimate.

Also look out for the badge of the Financial Services Compensation Scheme – as its name suggests, this is set up to pay out if a company goes wrong and leaves investors out of pocket.

• Treat unsolicited calls and emails with suspicion. Often people who have bought into one investment scheme will get calls about others – it may be that some companies sell their lists. There are also fraudsters who make a business out of offering to buy up failed investments – they typically ask for an upfront fee of some kind, then disappear. Do not agree to anything without doing some research first.

• Do not assume property is good security. Many schemes offer ownership of a leasehold in return for your cash, and it can be reassuring to know that you own the rights to a room or a piece of land. But as investors caught up in landbanking schemes can vouch, even property can be worthless if you can’t use it and no one else wants to buy it.

• Use a reputable financial adviser. “If you’re parting with any serious sums of money, it’s worth taking advice from a good professional,” says Daley. “Look for advisers who are chartered or certified, which means they’re qualified to a higher level.”